Oak barrel tannin and toasting temperature: Effects on red wine condensed tannin chemistry

Red wine is known to derive specific aromas and to have its color enhanced by oak wood compounds, but the effect of oak barrels on wine tannin chemistry is not well known. Cabernet Sauvignon wines were aged from 8 to 12 months in oak barrels made with three different ellagitannin levels (Tannin Potential, TP) and two toasting levels. Condensed tannin composition, activity and ellagitannin contents have been characterized using HPLC-DAD and protein precipitation. Red wines aged in high TP barrels contained more ellagitannins, condensed tannins with lower mass and lower pigmented tannins percentage than in low TP barrels. Red wines aged in high-temperature toasted barrels contained less ellagitannins, condensed tannins with higher mass and higher pigmented tannins percentage than in low-temperature toasted barrels. Combined effects of ellagitannin, toasting levels and aging have been identified. The selection of barrels for ellagitannin content and toasting temperature can be used to manage red wine development.